Enhanced demodulation-based technique for estimating the parameters of fundamental component in power systems

The recent introduction of smart grid concepts in power systems demands metering and monitoring equipments with great deal of flexibility. To achieve this, one heavily depends upon new generation of signal processing tools. Regarding low-cost and effective signal processing-based techniques for parameters estimation in smart grids, the estimation of power components when frequency deviates from its nominal value is a timely and important issue to be addressed. The authors outline a demodulation-based technique for estimating the amplitude, phase and frequency of the fundamental component of a power line signal. This technique makes use of a finite impulse response filter design method that efficiently allocates zeros over the unit circle of the z-plane so that the performance losses yielded by power frequency deviations can be minimised if the signal is corrupted by harmonics. Numerical results indicate that the proposed technique outperforms previous ones and can be a good candidate for measurement and monitoring in flexible power systems.